Juan Luis Lux Monroy was 32 when he disappeared from the Altar area of Pima County, Arizona. He was last seen on July 15, 2007, and the disappearance was not reported until January 22, 2010. Official records list the circumstances as unknown and the Pima County Office of the Medical Examiner logged the case as FSC MPR 1089.

At the time he vanished he was described as between 5 feet 2 inches and 5 feet 4 inches tall, slender, 120 to 140 pounds, with a scar at the right side of his mouth and another on his left arm. His hair and eye color were not recorded. He wore blue jeans, a blue polo shirt and a blue Tommy jacket, with black high-top shoes marked tractor #39 and white socks. He carried a backpack containing an extra pair of blue jeans, a multicolored plaid shirt, extra socks, maroon underwear and a light green towel.

Few details explain what happened after he was last seen. If anyone saw Juan in July 2007 in or near Altar, or has information about his movements, please come forward.